Variable-speed mechanism.



NO. 791,618. PATENTED JUNE 6, 1905.

. I. M. FOSTER. VARIABLE SPEED MECHANISM.

APPLICATION FILED NOV- 8,1904- Attorne lows:

Patented June 6, 1905.

PATENT OFFICE.

ISAAC M. FOSTER, OF WEST COVINGTON, KENTUCKY.

. VAHI ABLE-SPE ED MECHANISM.

SPECIFICATION forming partof Letters Patent N0.-791,618, dated June 6, 1905.

Application filed November 8, 1904. Serial No. 231.882.

To all whom it may concern:

Be it known that I, ISAAC M. FosTER, a citizen of the United States, residing at West Covington, in the county of Kenton and State of Kentucky, have invented certain new and useful Improvements in Variable- Speed Mechanism, of which the following is a specification.

My invention relates to apparatus for varying the speed of a machine by the application of power to it through different combinations of gear-wheels, the object being to provide a convenient means for forming a sufficient number of different combinations to give a machine the proper working speeds. Y

My invention consists in mounting the several gear-wheels in a manner and in providing such accessories that half the speed variations within the capacity of the machine may be obtained by the operation of a single lever and that all of them may be obtained by the operation of only two levers and in the combination and arrangement of parts, as will be more fully described herein.

' In the accompanying drawings, Figure 1 is a vertical section through the center line of the driving-shaft. Fig. 2is aninverted lan of my invention. Fig. 3 and Fig. 4 are en arged inverted plan views of part of the gear-sliding accessories. Fig. 5 is a vertical section on the line x :0 of Fig. 2. Fig. 6 is an enlarged sectional detail of part of the locking device for the wheel shown in Figs. 3 and 4-. Fig. 7 is an enlarged sectional detail of the wheel and part of the locking device. Fig. 8

is an enlarged plan of the wheel and, parts of p the cam-plate, showing the alinement of the various members. Fig. 9 and Fig. 10 are sections of the slotted portion of the cam-plate on the lines y y and z 2, respectively, of Fig. 2, further illustrating the shape of the slot.

The construction of my invention is as folconnected by means of the clutch 5. Inside.

the housing 2 the shaft carries the gearwheels 6, 8, 9, and 10 of different diameters and rigidly attached thereto. A driven shaft 11 is journaled in the housing at 12 and 'and'15, outside the housin are the arms 20,

which are rigidly connecte under the bottom of the housing by the transverse portion 21 and extend upward to carry the intermediate shaft 22, which is journaled at 23 therein. Rigidly mounted on the intermediate shaft 22, within the housing, are the small gearwheel 24 and the large gear-wheel 25, in mesh with the large gear-wheel 14 and the small gear-wheel 15, resdpectively. Between the ear-wheels 24 an 25 the gear-wheel 26. is eathered on the intermediate shaft 22 and may be placed in-mesh with any one of the "gear-wheels 6, 7, 8, 9, and 10 by swinging the arms 20, carrying the gear-wheel 26, far enough away from these gear-wheels to clear them in passing, sliding it along the shaft to a point opposite the gear-wheel desired in the combination, and then swinging the arms back, carrying the gear-wheel 26 into mesh with it.

The transverse portion 21 of the arms 20 has the pin 27 in its middle portion, and a cam-plate 28 is supported by the housing 2 at 29 and at 30 above the transverse portion of the arms. The cam-plate 28 is provided with the serpentine slot 31 for the guidance of the pin27 projecting upward into it and is confined by its supports 29 and 30 to motion parallel to the shafts 1, 11, and 22. This motion is imparted to it by means of the lever 32, connected by the link 33 to the rack 34, the small gear 35, in mesh with this rack, and the large gear 36, rigidly attached to the small gear concentric therewith andin mesh with the rack 37 on the front edge of the camplate. This differential gearing is provided to obviate the long swing which the lever 32 ugs 38, extending dgast its rear edge.

would require if directl connected to the cam-plate in throwing t e plate through its full stroke. This swing would be very objectionable in the long lever required when the counter-shaft is placed in the upper part of a room. The camlate 28 is cut away so it will not interfere with the arms 20 at any point of its stroke and is provided with the The cam-wheel 39, rigi y mounted on the portion of the shaft 40 extending below the housing, has the pivoted lugs 41 on its lower face adapted to be engaged by the lugs 38 on the cam-plate. The shaft 40 is ournaled in the housing 2 at 42 and 43, is supported by the head 44-, and carries the pinion 45, rigidly attached near the bearing 43. The pinion 45 is in mesh with the rack 46, which slides on the guide 47, and has arms 48, flanking the gear-Wheel 26, allowing it to revolve or be swung by the arms 20, but controlling its movement parallel to its shaft. The camwheel 39 has depressions 49 in its upper face to receive the locking-pin 50, extending through the housing, whereby the above-described mechanism may be held stationary. The locking-pin 50, which is attached to the lever 51, is held in the depression 49 by the spring 52 acting on the lever only when the pin 53, near one end of the lever, is in one of the depressions 54 in the cam-plate 28. The sides of the depressions 54 are inclined to the line of motion of'the cam-plate, so as to gradually raise the pin 53. The lever 32 is provided with an are having notches 55 and has suitable mechanism 56 for looking it in any one of the notches.

Beginning with the gear-wheel 26, in mesh with the gear-wheel 8, as shown, and unlocking the lever 32 and moving it continuously away from the housing 2, the cam-plate 28 will be moved in the same direction and the arms 20 will be caused by the sides of the slot 31 to swing the gear wheel 26 away from the gear-wheel 8 far enough to clear the adjacent larger gear-wheel 9. Meanwhile the pin 53 has been raised by the side of the depression 54 unlocking the cam-wheel 39. The lug 38 now engages the pivoted lug 41, the spring 42 yields until the lug 41 engages the cam-wheel rigidly at 57, when the camwheel revolves, acting through the pinion 45 and the rack 46 to slide the gear-wheel 26 op posite the gear-wheel 9. When this has been accomplished, the engaging portions of the lugs 38 and 41 have become parallel to the line of motion of the cam-plate and the camwheel- 39 ceases to revolve. The pin 53 begins to descend the side of the next depression 54, allowing the locking-pin 50 to enter the next depression 49 on the cam-wheel 39, preventing the gear-wheel 26 from leaving its new position longitudinally of its shaft. The part of the slot 31 now engaging the pin 27 causes it to swing the gear 26 into mesh with the gear 9, effecting the new combination. The lug 38 now disengages the pivoted lug 41, which is thrown into its radial position again by its spring 42 ready to be engaged by the lug 38 on its return, thus making the operation reversible at will. The lever 32 is locked in the next notch 55, holding the cam-plate and the arms 20 stationary, thus maintaining the gear-wheels in mesh.

It will be seen that by means of the mechanism above described any of the gear-wheels 6, 7, 8, 9, and 10 may be made to revolve the driven shaft 11 either through the gearwheels 24 and 14 or through the gear-Wheels 25 and 15, permitting ten different speeds of the driven shaft 11 to be obtained from one speed of the drivin -shaft 1 by the operation of the levers 17: and 32, which would operate through a comparatively short distance near the floor with the counter-shaft at a reasonable height. The sides of the slot 31 incline at a constantly-varying angle to allow the pin, 27 to assume its various positions, as is suggested by the sections shown in Figs. 9 and 10. The construction of the entire machine is such that the housing 2 forms a practically dust-proof casing and has the oil-basin 58 in its lower ortion for the lubrication of the gear-whee s.

Itis obvious that myinvention is adaptable for use with various forms of power-transmission mechanism and the precise construction here shown is not essential thereto ex cept as set forth in the following claims.

I claim 1. In variable-speed mechanism, a driving-shaft, gear-wheels thereon, means for retating the gearwheels, a pivoted arm, a shaft mounted in said arm, a gear-wheel thereon adapted to mesh with any one of the gear-wheels on said driving-sh aft, and a camplate adapted to operate said arm for the purposes specified.

2. In variable-speed mechanism, a driving-shaft, gear-wheels thereon, means for rotatin the gear-wheels, a driven shaft, a gearwheel thereon, a pivoted arm, an intermediate shaft mounted in said arm, a gear-wheel thereon, meshing with the gear-wheel on said driven shaft, a gear-wheel thereon adapted to transmit motion from any one of the said gears on said driving-shaft to said intermediate shaft, and a cam-plate adapted to operate said arm for the purposes specified.

3. In variable-speed mechanism, a driving-shaft, gear-wheels thereon, means for rotating said driving-shaft, a driven shaft parallel to said driving-shaft, a gear-wheel thereon, an arm pivoted concentric to said gearwheel, an intermediate shaft mounted in said arm parallel to said driving-shaft, a gearwheel thereon meshing with the gear-wheel on said driven shaft, and a gear-wheel thereon adapted to transmit motion from any one of said gear-wheels on said driving-shaft to If h n said intermediate shaft, and a cam-plate adapted to operate said arm for the purposes specified.

4. In variable-speed mechanism, a driving-shaft, gear-wheels thereon, means for operating the gear-wheels, a driven shaft parallel to said driving-shaft,-a gear-wheel thereon, an arm pivoted concentric to said gear-wheel', an intermediate shaft mounted in said arm parallel to said driving-shaft, a gear-wheel thereon meshing with the gear-wheel on said driven shaft, and a gear-wheel mounted thereon to slide lengthwise thereof," but to rotate therewith and to transmit motion from anyone of said gear-wheels on said driving-shaft to said intermediate shaft.

5. In a variable-speed mechanism, a driving-shaft, gear-wheels thereon, means for rotating the ear-wheels, a driven shaft parallel to said riving-shaft, a gear-wheel thereon, an arm pivoted concentric to said gearwheel, an intermediate shaft mounted in said arm parallel to said driving-shaft, a gearwheel thereon meshing with the gear-wheel on said driven shaft, and a gear-wheel mounted thereon to slide lengthwise thereof, but to rotate therewith and to transmit motion from any one of said gear-wheels on said drivin -shaft to said intermediate shaft, a cam-p ate adapted to swing said arm on its pivot to mesh and unmesh the gear-wheel slidably mounted on said intermediate shaft and means whereby said cam-plate slides said gear-wheel lengthwise of its shaft for the purposes specified.

6. In a variable-speed mechanism, a driving-shaft, gear-wheels thereon, means for rotating said gear-wheels, a driven shaft parallel to said driving-shaft, a gear-wheel thereon, an arm pivoted concentric to said gearwheel, an intermediate shaft mounted in said arm, parallel to said driving-shaft,- a gearwheel thereon meshing with the gear-wheel on said driven shaft and a gear-wheel thereon adapted to transmit motion from any one of said gear-wheels on said driving-shaft to said intermediate shaft, and a cam-plate confined to motion parallel to said shafts, adapted to swing said arm on its pivot to mesh and unmesh the gear-wheel slidaloly mounted on said intermediate shaft, a lug on said camplate, a cam-wheel adapted to be revolved intermittently by said lug, a pinion rigidly connected to said cam-wheel, a rack in mesh with said pinion, an arm on said rack engaging the gear-wheel on said intermediate shafts whereby said cam-plate slides said gearwheel lengthwise of said shaft for the purposes specified.

7. In a variable-speed mechanism, a driving-shaft, gear-wheels thereon, means for rotating the gear-wheels, a driven shaft parallel to said driving-shaft, a gear-wheel thereon, an arm pivoted concentric to said gear- Wheel, an intermediate shaft mounted in said arm parallel to said driven shaft, a gearwheel thereon meshing with the gear-wheel on the said driven shaft and a gear-wheel mounted thereon adapted to slide lengthwise thereof but to rotate therewith and to transmit motion from any one of the gear-wheels on said driving-shaft to said intermediate shaft, a cam-plate confined to motion parallel to said shafts and adapted to swing said arm on its pivot to mesh and unmesh the gear-wheel slidably mounted on said intermediate shaft, a lever differentially geared to said cam-plate, a lug on said plate, a camwheel adapted to be revolved intermittently by said lug, a pinion rigidly connected to said cam-wheel, a rack in mesh with said inion an arm on said rack en a in the earon said intermediate shaft whereby thecamplate slides the gear-wheel lengthwise of the shaft by the operation of said lever for the purposes specified.

8. ,In a variable-speed mechanism, a driving-shaft, means for rotating the shaft, earwheels rigidly mounted on said sha t, a driven shaft j ournaled parallel to said drivingshaft, gear-wheels loosely mounted thereon,

means for connecting said loosely-mounted gear-wheels rigidly to said driven shaft singly, arms pivoted concentric to said thereof but to rotate therewith, a cam-plate confined to motion parallel to said shafts,

and adapted to swing said arm on its pivot to mesh and unmesh the gear-wheel on said intermediate shaft with the gears on said driving-shaft a lug on said plate, a cam-wheel adapted to be revolved by said lug, a pinion rigidly connected to said cam-wheel, a rack to mesh with said pinion, an arm on said rack engaging the gear-wheel on'said intermediate shaft, a lever connected to said cam-plate and means for locking said lever whereby said gear-wheel, slidably mounted on said intermediate shaft, is meshed and unmeshed,

moved lengthwise on its shaft or maintained in mesh by the operation of said lever.

9. In a variable-speed mechanism, a driving-shaft, gear-wheels thereon, means for rotating said gear-wheels, adriven shaft parallel to said driving-shaft, a gear-wheel thereon, an arm pivoted concentric to said gearwheel, an intermediate shaft mounted in said arm parallel to said driving-shaft, a gearwheel thereon meshing with the gear-wheel on said driven shaft, a gear-wheel thereon adapted to transmit motion from any one of swing said arm, a lug on said plate, a cam wheel adapted to be revolved intermittently by said lug, a pinion rigidly connected to said cam-wheel, a rack in mesh with said pinion, an arm on said rack engaging the gear-wheel on said intermediate shaft, a lever connected to said cam-plate and means for locking the lever whereby the slidablyunounted gearwheel is meshed and unmeshed, moved lengthwise of its shaft or maintained in mesh by the operation of said lever.

10. In variable-speed mechanism, a driving-shaft, means for rotating said shaft, gearwheels rigidly mounted on said shaft, a driven shaft journaled parallel to said driving-shaft, gear-wheels loosely mounted thereon, means for connecting said loosely-mounted ear-wheels rigidly to said driven shaft sing ly, arms pivoted concentric to said loosely-mounted gear-wheels, an intermediate shaft journaled therein parallel to said driven shaft, gear-wheels rigidly mounted thereon meshing with the loosely-mounted gear-wheels on said driven shaft, and a gearwheel mounted thereon to slide lengthwise thereof but to rotate therewith, a cam-plate confined to motion parallel to said shafts and adapted to swing said arm on its pivot to mesh and unmesh the gear-wheel on said in termediate shaft with the gears on said driving-shaft, a lug on said plate, a cam-wheel adapted to be revolved by said lug, a pinion rigidly connected to said cam-wheel, a rack in mesh with said pinion, an arm on said rack engaging the gear-wheel on said intermediate shaft, a lever geared to said camplate, and means for locking the lever, whereby said slidably-mounted gear-wheel on said intermediate shaft is meshed and unmeshed, moved lengthwise on its shaft or maintained in mesh by the operation of said lever.

11. In variable-speed mechanism, a driving-shaft, gear-wheels thereon, means for rotating the gear-wheels, a driven shaft parallel to said driving-shaft, a gear-wheel thereon, an arm pivoted concentric to said gearwheel, an intermediate shaft mounted in said arm parallel to said driving-shaft, a gearwheel thereon in mesh with the gear-wheel on the driven shaft, and a gear-wheel thereon adapted to transmit motion from any one of the said gear-wheels on said driving-shaft to said intermediate shaft, a cam-plate confined to motion parallel to said shafts, adapted to swing said arm on its pivot to mesh and unmesh the slidably-mounted gear-Wheel 011 said intermediate shaft, a lug on said camplate, a cam-Wheel, a lug pivoted thereon adapted to be engaged by the lug on said cam-plate and to engage said cam-wheel to rotate it, a pinion rigidly secured to said camwheel, a rack in mesh with said pinion, an arm on said rack engaging the gear-wheel on said intermediate shaft, a lever connected to the camplate and means for locking the lever.

12. In variable-speed mechanism, a driving-shaft, gear-wheels thereon, means for retating the gear-wheels, a drivensha'ft parallel to said driving-shaft, a gear-wheel thereon, an arm pivoted concentric to said gearwheel, an intermediate shaft mounted in said arm parallel to said driving-shaft, a gear-wheel thereon meshing with the gearwheel on said driven shaft, and a ge:n-\vheel thereon, adapted to transmit motion from any one of the said gear-wheels on said driving-shaft to said intermediate shaft, a camplate confined to motion parallel to said shafts adapted to swing said arm on its pivot to mesh and unmesh the gear-wheel slidably mounted on said intermediate shaft, a lug on said cam-plate, a cam-wheel, means for automatically locking and unlocking the camwheel, a pinion rigidly connected to said cam- Wheel, a rack in mesh with said pinion, an arm on said rack engaging the gear-wheel on said intermediate shaft, a lever connected to said cam-plate and means for locking the lever.

13. In variable-speed mechanism, a driving-shaft, gear-wheels thereon, means for rotating the gear-wheels, a driven shaft parallel to said driving-shaft, a gear-wheel thereon, an arm pivoted concentric to .aid gearwheel, an intermediate shaft mounted in said arm parallel to said driving-shaf t, a gear-wheel thereon meshing with the gearwheel on said driven shaft, and a gear-wheel thereon adapted to transmit motion from. any one of the gear-wheels on said drivingshaft to said intermediate shaft, a cam-plate confined to motion parallel to said shafts adapted to swing said arm on its pivot to mesh and unmesh the gear-wheel slidahly mounted on said intermediate shaft, a lug on said cam-plate, a cam-wheel having a depression therein, a locking-pin, a spring engaging said locking-pin in said depression, means whereby said plate disengages said pin. from within said depression, a pinion rigidly connected to said cam-wheel, a rack in mesh with said pinion, an arm on said rack engaging the gear-wheel on said intermediate shaft, a lever connected to said plate and means for locking the lever.

14. In variable-speed mechanism, a driving-shaft, gear-wheels thereon, means for rotating the gear-wheels, a driven shaft parallel to said driving-shaft, a gear-wheel thereon, an arm pivoted concentric to said gearwheel, an intermediate shaft mounted in said arm parallel to said driving-shaft, a gear-wheel thereon meshing with the gearwheel on said driven shaft, and a gear-wheel thereon adapted to transmit motion from any one of the said gear-wheels on said driving-shaft to said intermediate shaft, a camplate confined to motion parallel to said shafts adapted to swing said arm on its pivot to mesh and unmesh the sli lably-mounted gear-wheel on said intermediate shaft, a lug on said cam-plate, a cam-wheel, means for' said cam-wheel, a rack in mesh with said pint ion, an arm on said rack engaging the gearwheel on said intermediate shaft, a rack on said cam-plate, a gear in mesh with said rack, a smaller gear rigidly secured to said gear concentric thereto, a shorter rack in mesh with said smaller gear, a lever, means for locking said lever, and a link pivoted to the lever and to said shorter rack for the purposes s ecified.

15. n variable-speed mechanism, a driving-shaft, gear-wheels thereon, means for rotating the gear-wheels,- a driven shaft paral+ lel to said driving-shaft, a gear-wheel thereon, an arm pivoted concentric to said gearwheel, an intermediate shaft mounted in said arm parallel to said driven shaft, a gearwheel thereon in mesh with the gear-wheel on said driven shaft, and a gear-wheel thereon adapted to transmit motion from any one of the gear-wheels on said driving-shaft to said intermediate shaft, a cam-plate confined to motion parallel to said shafts, having surfaces inclined to the line of said motion and adapted to swing said arm on its pivot to mesh and unmesh the gear on said intermediate shaft, a lug on said cam-plate, a cam-Wheel having a depression therein, a locking-pin, a lever attached thereto, a spring engaging said locking-pin in said depression, a pin attached to said lever and engaging said inclined surface on said cam-plate as, and for, the purposes specified.

16. In variable-speed mechanism, a driving-shaft, means for rotating the shaft, gearwheels rigidlymounted on said shaft, a driven shaft j ournaled parallel to said driving-shaft, gear-wheels loosely mounted thereon, means for connecting said loosely-mounted gearwheels rigidly to said driven shaft singly, arms pivoted concentric to said looselymounted gear wheels, an intermediate shaft journaled therein parallel to said driven shaft, a gear-wheel thereon meshing with the gear-wheel on said driven shaft, and a gearwheel mounted thereon to slide lengthwise thereof but to rotate therewith, a cam-plate confined to motion parallel to said shafts and adapted to swing said arms to mesh and unmesh the gear-wheel slidably mounted on said intermediate shaft with the gears on said driving-shaft, a rack on said cam-plate, a

gear in mesh with said rack, a smaller gear rigidly secured to said gear concentric thereto, a shorter rack in mesh with said smaller gear, a lever, means for locking the lever, a link pivoted to said lever and to said shorter rack, a lug on said cam-plate, a cam-wheel, a pivoted lug thereon adapted to be engaged by the lug on said cam-plate and to engage said cam-Wheel to rotate it, a pinion rigidly connected to said cam-wheel, a rack in mesh with said pinion, an arm on said rack engaging the ear-wheel slidably mounted onsaid interme iate shaft, whereby said gear-Wheel is successively unmeshed, moved lengthwise of its shaft, meshed, and maintained in mesh by the operation of the lever connected to' the cam-plate.

17 In variable-speed mechanism, a driving-shaft, gear-wheels thereon, means for rotating the gear-wheels, a driven shaft parallel to said driving-shaft, a gear-wheel thereon, an arm pivoted concentric to said gearwheel, an intermediate shaft mounted in said arm parallel to said driven shaft, a gearwheel thereonmeshing with the gear-wheel on said driven shaft, and a gear-wheel mounted thereon to slide lengthwise thereof, but to rotate therewith, a cam-plate confined to mo- 'tion parallel to said shafts and adapted to swing said arm to mesh and unmesh the gearwheel slidably mounted on said intermediate shaft with the gears on said driving-shaft, a rack on said cam-plate, a gear in'mesh with said rack, a smaller gear rigidly secured to said gear concentric therewith, a shorter rack in mesh with said smaller gear, a lever, means for locking said lever, a link pivoted to said lever and to said shorter rack, a lug on said cam*plate, a cam-wheel, a lug pivoted thereon yieldably held radially thereof and adapted-to be engaged bythe lug on said cam-plate re ardless of the direction of motion of said p ate parallel to the shafts, a pinion rigidly connected to said cam wheel, a rack in mesh with said pinion, an arm on said rack engaging the gear-wheel on said intermediate shaft and means for automatically locking and unlocking said cam-wheel for'the purposes specified.

18. In variable-speed mechanism, a driving-shaft, gear-wheels thereon, means for rotating the gear-wheels, a driven shaft arallel to said driving-shaft, a gear-wheel t ereon, an arm pivoted concentric to said gear-wheel an intermediate shaft mounted in said arm parallel to said driven shaft, a gear-wheel thereon meshing with the gear-wheel on said driven shaft, and a gear-wheel mounted thereon to slide lengthwise thereof but to rotate therewith, a cam-plate confined to motion parallel to said shafts having surfaces inclined to the line of said motion and adapted to swing said arm to mesh and unmesh the gearwheel on said intermediate shaft with the gears on said driving-shaft, a rack on said cam-plate, a gear in mesh with said rack, a smaller gear rigidly secured to said gear concentric therewith, a shorter rack in mesh with said smaller gear, a lever, means for locking said lever, a link pivoted to said lever, and to said shorter rack, a lug on said cam-plate, a cam-wheel having a depression therein, a lug pivoted thereon yieldably held radially thereof and adapted to be engaged and disengaged by the lug on said cam-plate regardless of the direction of motion of said cam-plate parallel to the shafts, a locking-pin, a lever attached thereto, a spring engaging said loeking-pin in said depression, a pin attached to said lever and engaging said inclined surface, a pinion ing-shaft, means for rotating the shaft, gearwheels rigidly mounted thereon, a driven shaft, gear-wheels loosely mounted thereon, means for rigidly attaching the looselymounted gear-wheels to said driven shaft singly, arms pivoted concentric to said loosely mounted gear-wheels, an intermediate shaft journaled therein, gear-wheels rigidly mounted on said intermediate shaft and in mesh with said loosely-mounted gear-wheels, a gear mounted on said intermediate shaft to slide longitudinally thereof but to rotate therewith and adapted to mesh with any one of the gear-wheels rigidly mounted on said driving-shaft and transmit motion to said intermediate shaft, a cam-plate confined to motion parallel to the shafts, having surface inclined to the line of said motion and adapted to swing said arm on its pivot to mesh and unmesh the gear slidably mounted on said intermediate shaft, a rack on said plate, a gear in mesh with said rack, a smaller gear rigidly connected to said gear concentric therewith, a shorter rack in mesh with said smaller gear, a lever, means for locking the lever, a link pivoted to said lever and to said shorter rack, a lug on said camplate, a cam-wheel having a depression therein, a lug thereon yieldably held radially thereof adapted to be engaged and disengaged by the lug on said cam-plate regardless of the direction of motion of said plate parallel to said shafts, a locking-pin, a lever connected thereto, a spring engaging said locking-pin in said depression, a pin connected to said lever and engaging said inclined surface, a pinion rigidly connected to said cam-wheel, a rack in mesh with said pinion having an extension engaging the gear-wheel slidably mounted on said intermediate shaft substantially as, and for, the purposes speeified.

ISAAC M. FOSTER.

Witnesses JAMES N. RAMSEY, CLARENCE L. PERDEW. 

